The panel of judges, presided over by Barita Saragih, said the defendant was guilty of violating Article 154 of the Criminal Code on insulting, or expressing enmity toward or hatred of, the Indonesian government.

Achin was also found guilty of violating Article 66 of Law No. 24/2009 on the state flag, language, emblems and national anthem.

"Aggravating factors include his inciting public anger and offence among Indonesians. Mitigating factors include his polite demeanour during the trial, his honesty and apology and remorse" Barita said when reading out the verdict.

The case involving the operations manager of PT Kreasijaya Adhikarya, a Malaysian palm oil processing company, began on Aug. 16 when the company's employees were preparing a flag for the Independence Day ceremony.

Achin asked one of his subordinates, I Made Cipta Kusuma, whether they had a new flag or not. "If you do not have a new flag, just use my white underwear. For the red you can ask my wife," Achin reportedly told his workers.

His comment, which was meant as a joke, made its way to the Dumai City Council and into the media.

The police arrested Achin several days later under public pressure and proceeded with the case.

Prosecutor Ary Supendi demanded a two-and-a-half-year jail term for the offences. He did not say whether he accepted the verdict or would file an appeal. "I will have to coordinate with my superiors to decide the next legal step," he said.

Achin's lawyer, Muhammad Hatta, was also considering the verdict saying he was disappointed.

"Achin actually hoped to be acquitted because he did not intend to insult the flag. We are disappointed with the verdict but we respect the judge's decision," he said. "I will consult with my client. We still have one week to consider the verdict."

The trial was held under tight security by Dumai Police personnel as the trial had attracted extensive public attention.